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Altera_Forum
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10 years ago

Reference clock for Cyclone V GX Transceiver Native PHY receiver source?

The documentation doesn't explicitly say it (or if it does, I can't find it), but must the source for the reference clock for the C V's Transceiver Native PHY receiver come from the REFCLK0 pin pair, or can it be sourced from inside the FPGA?

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  • Altera_Forum's avatar
    Altera_Forum
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    Well, the C5 Transceiver handbook says that the transceivers can be clocked by a fractional-PLL (in integer mode), but the fitter seems to choose the fPLL's _input_ as the clock, not the fPLL clock output I explicitly coded ...